Glucosamine and chondroitin sulfate supplementation to treat symptomatic disc degeneration: Biochemical rationale and case report

BACKGROUND: Glucosamine and chondroitin sulfate preparations are widely used as food supplements against osteoarthritis, but critics are skeptical about their efficacy, because of the lack of convincing clinical trials and a reasonable scientific rationale for the use of these nutraceuticals. Most trials were on osteoarthritis of the knee, while virtually no documentation exists on spinal disc degeneration. The purpose of this article is to highlight the potential of these food additives against cartilage degeneration in general, and against symptomatic spinal disc degeneration in particular, as is illustrated by a case report. The water content of the intervertebral disc is a reliable measure of its degeneration/ regeneration status, and can be objectively determined by Magnetic Resonance Imaging (MRI) signals. CASE PRESENTATION: Oral intake of glucosamine and chondroitin sulfate for two years associated with disk recovery (brightening of MRI signal) in a case of symptomatic spinal disc degeneration. We provide a biochemical explanation for the possible efficacy of these nutraceuticals. They are bioavailable to cartilage chondrocytes, may stimulate the biosynthesis and inhibit the breakdown of their extracellular matrix proteoglycans. CONCLUSION: The case suggests that long-term glucosamine and chondroitin sulfate intake may counteract symptomatic spinal disc degeneration, particularly at an early stage. However, definite proof requires well-conducted clinical trials with these food supplements, in which disc de-/regeneration can be objectively determined by MRI. A number of biochemical reasons (that mechanistically need to be further resolved) explain why these agents may have cartilage structure- and symptom-modifying effects, suggesting their therapeutic efficacy against osteoarthritis in general

Validity and interobserver agreement of a new radiographic grading system for intervertebral disc degeneration: Part I. Lumbar spine

Many different radiographic grading systems for disc degeneration are described in literature. However, only a few of them are tested for interobserver agreement and none for validity. Furthermore, most of them are based on a subjective terminology. The aim of this study, therefore, is to combine these systems to a new one in which all subjective terms are replaced by more objective ones and to test this new system for validity and interobserver agreement. Since lumbar and cervical discs need to be graded differently, this study was divided into the present Part I for the lumbar and a Part II for the cervical spine. The new radiographic grading system covers the three variables “Height Loss”, “Osteophyte Formation” and “Diffuse Sclerosis”. On lateral and postero-anterior radiographs, each of these three variables first has to be graded individually. Then, the “Overall Degree of Degeneration” is assigned on a four-point scale from 0 (no degeneration) to 3 (severe degeneration). For validation, the radiographic degrees of degeneration of 44 lumbar discs were compared to the respective macroscopic ones, which were defined as “real” degrees of degeneration. The agreement between observers with different levels of experience was determined using the radiographs of 84 lumbar discs. Agreement was quantified using quadratic weighted Kappa coefficients (Kappa) with 95% confidence limits (95% CL). The validation of the new radiographic grading system revealed a substantial agreement between the radiographic and the “real” macroscopic overall degree of degeneration (Kappa=0.714, 95% CL: 0.587–0.841). The radiographic grades, however, tended to be slightly lower than the “real” ones. The interobserver agreement was substantial for all the three variables and for the overall degree of degeneration (Kappa=0.787, 95% CL: 0.702–0.872). However, the inexperienced observer tended to assign slightly lower degrees of degeneration than the experienced one. In conclusion, we believe that the new radiographic grading system is an almost objective, valid and reliable tool to quantify the degree of degeneration of individual lumbar intervertebral discs. However, the user should always remember that the “real” degree of degeneration tends to be underestimated and that slight differences between the ratings of observers with different levels of experience have to be expected